Here you go Sir: https://operatingfluids.mercedes-ben...heet/229.52/en

 

And here is the page that tells you which oil spec is approved for which engine type: https://operatingfluids.mercedes-ben.../engine-oil/en (click on the first link, Sheet 223.2).

 

OK, thanks! That's the one I was looking for. I was thinking it was just another list of suppliers of 223.2 rated oils.

 

In addition to a slightly better fuel economy requirement, MB 229.52 approval requires that the oils have a considerably better oxidation stability than MB 229.51 oils, which is the problem when biodiesel ends up in the sump (the oil oxidizes and is no longer able to provide adequate lubrication and thus engine protection).

0W-40 is thicker than 0W-30 at operating temperatures and thus flows less readily. As the oil is the primary means of cooling the engine internals, less oil flow creates hot sports within the engine and in turn leads to premature equipment failures (various bearings for example). There have been ZERO reports of 0W-30 oil being inadequate - as in not thick enough - for all operating conditions of the OM642 in all climates. Putting in thicker oil than required in this case only shortens the life of the engine and increases fuel consumption.

CK-4 is a minimum standard for commercial vehicles and off-road equipment, just like the API Sx standards for gasoline engines. Trucks and bulldozers are not subject to the same emission requirements as passenger vehicles and their emission control systems are designed differently so it is not applicable here in any way, just like a gasoline oil with an API SN rating does not necessarily meet Porsche A40 or MB 229.5 lubrication standards for example.

MB 228.51 is a very oil spec and no longer applicable. In your particular case (i.e. 15-20-year-old engine in which you could use MB 228.51 oils when it was introduced), the oil spec change is necessitated not by the engine itself but rather by the chemical makeup of the diesel fuel that you're now putting in, which is not the same as it was 15-20 years ago. If you had pure dinosaur juice diesel (B0) you could continue to use an MB 228.51 oil with no ill effects, but unfortunately B0 is not what comes out of the pumps these days.

 

Thanks, but takes me back to my original question. Seems 229.52 is recommended for all "Cars" but the note is about fuel mileage (A concern to MB to make their CAFE numbers.)
The same engine in a Sprinter with very similar DPF/Exhaust system year by year, shows 228.51 229.31/51/52

So, setting aside fuel milage, and focusing on longevity of the engine and DPF, . . . .

. . . Anyone have a recommendation (with rationale) which oil is best.

EDIT: Just read your last post;
The M642 was sold for many years running 0W40, so why would you think that doing so might cause hot spots? (Note: Current M1 X3 ESP 0W40 is showing 229.51/52)
While heavy equipment and large trucks engines are different, a lot of light and medium trucks use automotive like engines and emissions system, (Including Sprinters with M642 engines)
Yet, in these applications MB recommendations include 228.51 (Which carries a specific "diesel" certification missing from most all 229.51/52 oils.)

 

It's in the URL I posed above in post #27 - https://operatingfluids.mercedes-ben.../engine-oil/en. The first link on that page - Sheet 223.2 - is the list of Mercedes engines and the oils approved for each.

 

Yep. saw that mentioned in a later post, but looks like I was editing (slowly since I am on a bunch of calls) and our posts overlapped.

My edit to the last post.

 

The link I gave is starting page with links to specifics.
I know it can be a bit overwhelming to start, but learn how to scroll to what you need and check it before each oil purchase to check for updates.
Approved oils come and go, so what you used for last change might no longer be considered good.
That happen to popular Mobi1, who seems to reformulate the oils to come back on the wagon.
As what oil is the best, I posted lab results for Motul, that I considered the best. There is no independent research who will answer that question for you.
You can find comparing mechanical characteristics on "Project Farm" youtube channel, but that is all I could find.

 

Pennzoil Platinum Euro L Full Synthetic 5W-30, MB 229.51 rated, $26.44 for a 5 quart bottle at Wal*Mart.

Valvoline European Vehicle Full Synthetic XL-III SAE 5W-30, MB 229.52 rated, price varies from $78.72 to $102.57 for a case of 3 - 5 quart bottles from Amazon.

Both carry an ACEA C3 rating. According to ACEA, C-grade oils are stable, low-friction, and low-viscosity oils. They are used in vehicles equipped with diesel particulate filters (DPFs) and three-way catalytic converters (TWCs). C-grade oils are also used in high-performance diesel and petrol engines that require the use of oils with low levels of SAPS content.(Valvoline)

Rationale: best specs for the buck. SAE -30 oils are recommended in (my) operator's handbook without an upper ambient temperature limit. As long as you can maintain pressure, you will be fine.

 

I guess a more direct question is what usually fail in these engines, and what oil addresses that issue without being too bad on the DPF?

I have assumed it was Cams and Cam Chain stretch/wear, followed by less frequent bore scoring (and seeming rare bearings).

Doing all I can to keep good fuel in it. (Buy only at high volume stations, avoiding 20% Bio when I can and getting D2 when I can.
Adding a dose of PowerServ every few tanks.
Try to keep short runes to a minimum, etc.

 

Well, I just scored 10 Qts of M1 0W40 X3 ESP for about $8 a qt after discounts, so this change is good.

Double check this; Pennzoil Platinum Euro L Full Synthetic 5W-30, It shows 229.5 not 229.51

 

Where did you find that? I checked a few sources and decided it was about twice what I've been paying.



https://www.walmart.com/ip/Pennzoil-...sRedirect=true

 

You are right.
Didn't see it on the Pennzoil site.
Seems they have a different site for their Euro oils.
There is also an LX that is 0w30 and 229.31/51/52.

My oil was from Autozone.
They have a deal to get 5 qts plus a filter for 43.
I needed the filters anyhow.
You usually get an additional $5 to $10 discount for a first order.
I had to try a few times to let me pick the right oil, as it keeps sending me back to other oils.
There is a button to swap products.
It even picked the wrong filter, and I had to swap it out also.

 

https://www.autozone.com/motor-oil-a...rt/1177215_0_0

 

Sorry just got on, the first choice in the link shows engine specific oils. For some reason cant list the actual results.

 

No you are not correct in that statement. CK4 is required by on the road fully emissions standard diesel trucks with the same requirements as other passenger vehicles. Every light duty (medium duty sort of) diesel truck on the market right now in the US requires CK4, is subject to the same engine standards as the passenger cars and uses DPF/SCR/DEF. The only difference is no required fuel mileage rating due to being used for towing. Except in the 1500 (1/2ton) size flavors.

Just to be clear I am not saying 15w40 is the best oil for mercedes OM651 or 642, can only recommend what MB does technically as I have not tried the others in my car but do run them in my cummins 3500 except in that thing I do 15w40 conventional with 12-15k mile change intervals. Have about 168k miles and just shy of 4k hours on it right now.

 

Look at the temperature charts for your vehicle, 0 to 15 weight oils depending on what you can get (primarily) and what ambient temperature is will decide what you can run. Bought mine used at 76k miles and it used 5w40 .51 oils its whole life from dealer, I swapped to 5w30 .52 oils and have 95k miles now on it. From the sounds of it the v6 needs .52 due to jelling issues.

That is true for post 2016 models om642 and the ones listed in the spec sheet (which probably covers most of the ones sold in US, not sure). More then likely when they found out the engine oil was jelling and killing the engines then made that change.

 

BINGO
Diesel oil for diesel engines. If it doesn't say CK-4 on the bottle it's not going in my engine. MB used to be aware of this obvious fact but then they got carried away with trying to chase down 1% fuel economy improvement and protecting the all mighty DPF at all cost, even if it means early engine failure.
Just to be clear, are you talking about the same engineer that stuffed oil cooler and it's sketchy gaskets underneath the intake manifolds? The brilliant minds that decided the om642 doesn't need an oil pressure warning light? Are these the genius engineers you're putting all your faith in!?!?

I've got a bridge to sell you.

 

Can you elaborate @tjts1 on CK-4. First I'm hearing about this. I'm using this Liqui-Moly https://www.genracer.com/liqui-moly-...iters-lm20448/ and it says gasoline + diesel engines, but your comment gave me pause.


And decided not to use oil dipsticks. And decided that transmission fluid was lifetime fill.

 

CK-4 is the current industry wide diesel engine oil standard put out by the API (American petroleum institute).


Almost every engine oil manufacturers has one or more CK-4 oils available on the market. The standard is updated every few years so CK-4 supercedes CJ-4 which supercedes CI-4... you get the idea. There is a separate gasoline engine oil standard put out by the API currently called SN which supercedes SM. Some oils carry both CK-4/SN labels. CK-4 diesel oils are designed to work with DPF.
​​​​​​
I'm not advocating for one particular oil brand or viscosity, rather that the oil going into a diesel engine is engineered to work in a diesel engine. MB 229.xx oils are designed for gasoline engines. This is why you'll have a hard time finding an oil that has both 229.xx and CK-4 labels. For example:

"API SN SM, MB 229.31, MB 229.51, MB 229.52" but no CK-4 because it doesn't meet the minimum requirements for a diesel engine oil. It's a gasoline engine oil yet people still pour it into their diesel. Mobil makes some excellent CK-4 diesel oils but this is not one of them.